Convicted College Grad Says Trying to Join ISIS Was 'More About Helping Others'

— -- In his first interview with ABC News' Diane Sawyer today, Muhammad Dakhlalla, the 24-year-old former honor student now in prison for trying to join ISIS, said the terrorist videos he'd watched with girlfriend Jaelyn Young seemed to promise a life of service and certainty.

"These propaganda videos that we were watching, that's how they showed themselves, as helping out other people, you know," Dakhlalla said.

Before their 2015 arrest and subsequent guilty pleas, Dakhlalla and Young were honor students at Mississippi State University. He'd been accepted into a graduate program after graduating cum laude with a degree in psychology. He also played soccer. Young, a college sophomore, had been a cheerleader in high school.

They both were raised in apparently stable families. Dakhlalla's father is a math tutor. Young's father is a police officer and a military veteran.

Now, Dakhlalla and Young are imprisoned, having pleaded guilty earlier this year to charges of providing material support to ISIS. Dakhlalla is serving eight years in federal prison. Young is serving 12 years.

Dakhlalla told ABC News' Diane Sawyer today in his first interview that he and Young met at the university. He said she was his first serious girlfriend though he said that, at the time, he had fallen into a depression.

Dakhlalla, a Muslim, said that Young was curious about the Islamic faith although she had been raised Christian. He said together they watched ISIS videos online.

"It was more about helping others ... rebuilding towns and feeding the poor and things like that," he said. "It looked like they were distributing, like, bags of food to people that don't have any way of having food."

He said he'd heard about ISIS beheading aid workers and journalists but had never seen those videos.

"We thought at that time, 'Oh surely they (the media) must be, you know, faking everything,'" he said. "The American media must be faking everything."

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The students sent messages to who they thought were ISIS recruiters but who were in fact FBI agents.

Young explained to the person she thought was an ISIS recruiter that she was attempting to go to Syria with a "brother," identified as Dakhlalla, who was 22 at the time.

Young said the two would have to have an Islamic marriage in order to travel together. She also wrote that she had math and chemistry skills and her partner was good at computer science and media. They could help the group, she said, they just needed assistance getting to Syria through Turkey.

The couple got as far as an airport in Columbus, Mississippi, in early August 2015 in hopes of heading to Turkey, but federal agents were waiting for them, according to court records.

It wasn't just Young sending messages online. In one of Dakhlalla's messages, he talked about being a mujahedeen fighter.

According to court documents, he wrote: "I wish to be a mujahid akhi. I am willing to fight. I want to be taught what it really means to have that heart in battle!"

He told Sawyer today that he was just trying to convince the recruiters that he could be strong. Dakhlalla said he did not want to kill Americans. He said he wanted to work in public relations "to clear up the name of Islam."

"It was more just like, 'Hey, you know, I wanna help as much as I can," he said.

Daklalla said his perspective on ISIS had changed from what what he'd seen on those videos.

"If I was actually going to arrive there (Syria), I would have seen a totally, completely different picture of what ISIS really is," he said. "It wasn't until I got arrested that I saw the reality of what ISIS is."